Related Experiment Video
Updated: Aug 15, 2026

Analyzing Large Protein Complexes by Structural Mass Spectrometry
Published on: June 20, 2010
Identification of proteins in complexes by solid-phase microextraction/multistep elution/capillary
1Department of Molecular Biotechnology, University of Washington, Seattle 98195-7730, USA.
Abstract:
A method to directly identify proteins in complex mixtures by solid-phase microextraction (micro-SPE)/multistep elution/capillary electrophoresis (CE)/tandem mass spectrometry (MS/MS) is described. A sheathless liquid-metal junction interface is used to interface CE and electrospray ionization MS/MS. A subfemtomole detection limit is achieved for protein identification through database searching using MS/MS data. The SPE serves as a semiseparation dimension using an organic-phase step-elution gradient in combination with the second separation dimension for increased resolving power of complex peptide mixtures. This approach improves the concentration detection limit for CE and allows more proteins in complex mixtures to be identified. A 75-protein complex from yeast ribosome is analyzed using this method and 80-90% of the proteins in the complex can be identified by searching the database using the MS/MS data from a complete analysis. This multidimensional CE/MS/MS methodology provides an alternative to multidimensional liquid chromatography/MS/MS for direct identification of small amounts of protein in mixtures.
More Related Videos
14:58Identification of Protein Complexes in Escherichia coli using Sequential Peptide Affinity Purification in Combination with Tandem Mass Spectrometry
Published on: November 12, 2012
10:05Large-scale Top-down Proteomics Using Capillary Zone Electrophoresis Tandem Mass Spectrometry
Published on: October 24, 2018
Related Concept Videos
Electrospray Ionization (ESI) Mass Spectrometry
ESI utilizes electrical energy to transfer ions from the liquid phase of the sample into the...
Peptide Identification Using Tandem Mass Spectrometry
This technique helps gather information regarding the protein from which the peptide was obtained and to study the peptides’ amino acid sequence. Identifying peptides from a complex mixture is an important component of the growing field of...
Mass Spectrometry: Complex Analysis
GC–MS is a powerful hyphenated method commonly used in forensics and environmental...
Tandem Mass Spectrometry
Electrophoresis: Overview
There...
Capillary Electrophoresis: Applications
Capillary zone electrophoresis (CZE) separates ionic components based on their electrophoretic mobility. It has been used to separate proteins, amino acids,...